Cellular and humoral immune responses to purified lens crystallins were examined in genetically-defined inbred strains of mice. Primed mice produced small, yet significant, cellular responses to the immunizing crystallins when tested in an in vitro proliferation assay. Crystallins from either mouse (allogeneic) or calf (xenogeneic) were active in the stimulation of these cellular responses. Sera of the immunized mice contained specific antibody activity to the tested crystallins. In other experiments, different strains of mice were immunized against purified retinal S-antigen. Preliminary results indicate that the immunized mice produced both cellular and humoral responses to the S-antigen. No pathologic changes (uveitis) have been observed in the eyes of these animals as of yet.